ABSTRACT Over 100 million Americans suffer from high blood pressure and thus are at increased risk for cardiovascular disease and premature morality. Evidence supports the DASH (Dietary Approaches to Stop Hypertension) dietary pattern to reduce blood pressure. DASH is rich in fruits and vegetables, legumes, lean protein, and low- fat dairy, and reduced in red meats, sweets and processed foods. In the past 20 years, numerous trials have demonstrated the blood pressure-lowering effects of DASH across a diverse range of populations. As such, DASH is part of national dietary and blood pressure guidelines. Despite this strong evidence, fewer than 1% of U.S. adults with high blood pressure fully meet DASH guidelines. Like most efficacious interventions, the rate- limiting step involves dissemination. Behavioral trials testing DASH have been delivered primarily in-person, an approach that is effective but not accessible to the broader population. Innovative and accessible strategies to disseminate DASH, such as digital health, are critically needed. To address this need, we developed and tested the feasibility of a 3-month digital health intervention called DASH Cloud. The DASH Cloud intervention asked participants to track their diet daily using a commonly-used commercial tracking app with an extensive nutrient database. Our intervention technology platform extracted food and nutrient data from the app using an application programming interface (API). Each day, using this API software, we compared individual participant?s nutrient intake to the recommended levels in the DASH diet. We then processed the data against an algorithm and sent automated text messages to each participant with information on DASH diet adherence and diet tips. Results indicated that we successfully recruited and retained individuals with elevated blood pressure, achieved high engagement with daily diet tracking and saw positive changes in diet quality. Based on the results of the feasibility trial, we will improve upon the personalization of the automated text messages and include a scalable and responsive way of delivering coaching, based on diet data received in the app. The efficacy of this approach will be tested via a fully-powered 12-month randomized controlled trial, DASH Cloud. The trial will examine the effects of the intervention on changes in dietary quality and blood pressure among men and women with high blood pressure, using the new blood pressure guidelines for nonpharmacological treatment. The primary outcome is 6-month change in DASH adherence, as measured by 24-hour recalls. We will also measure DASH adherence at 12-months post-randomization. Secondary outcomes include changes in blood pressure and other physiological outcomes (e.g. weight, lipids, glucose). The scientific premise of this proposal represents establishing the efficacy of a previously-deemed feasible approach for disseminating the DASH diet. With the millions of Americans in dire need of nonpharmacological treatments for blood pressure, the public health impact of disseminating the DASH Cloud intervention could drastically reduce the incidence of cardiovascular disease. The findings from this study prepare us for a future implementation trial, testing the potential to implement DASH Cloud within clinics and other healthcare institutions, yielding a wider dissemination of this evidence-based intervention.